Effect of processing conditions on the content of cis/trans carotene isomers as provitamin A carotenoids in Korean sweet potato varieties.

The present investigation intends to evaluate the changes in the content of cis/trans carotene isomers as provitamin A carotenoids by steaming and roasting processes in the roots of four Korean sweet potato varieties viz. Shinzami, Younwhangmi, Chuwhangmi and Jinhongmi using a liquid chromatography with diode array detection and the negative ion atmospheric pressure chemical ionization mass spectrometric (LC-DAD-APCI/MS) method and UV spectral pattern library created from several reference data. Except Shinzami, the content of all trans ß-carotenes was found to slightly decreased or remained constant when steamed or roasted. The content of cis α-/ß-carotenes was potentially increased about 2-fold or greater when raw or steamed and the content was slightly decreased while roasted. In Chuwhangmi, the content of 13-cis α-carotene and all trans α-carotenes were rapidly increased when steamed and slightly decreased when roasted. Chuwhangmi exhibited 27.2 mg/100 g DW content of all trans ß-carotenes when roasted and thus, it was considered as a relatively superior cultivar.

Facile water promoted synthesis of 1,2,3-triazolyl dihydropyrimidine-2-thione hybrids - highly potent antibacterial agents.

An elegant and efficient synthesis of hitherto novel 1,2,3-triazolyl dihydropyrimidine-2-thione hybrids has been accomplished for the first time in a green solvent viz. water. The hybrid molecules exhibit significant antibacterial activity when screened against four human pathogens viz. Streptococcus pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi. In comparison to the commercially marketed tetracycline, some of them were equally potent and a few more potent.